Title IX is an obstacle for some. It's not for the schools I mentioned, and we probably could add Georgia to those three.
That said, we can't just conclude, absent evidence, that Title IX is the reason Stanford hasn't launched a program -- it could be related to concerns about recruiting and game travel and scheduling costs until California/Oregon/Arizona schools achieve critical mass. And to assume that "Florida State has been rumored to be ready to go" + "no FSU program" = "Title IX issues" is a reach, at best. Any number of things could be at play -- decisions about a facility, hiring the right coaches, etc.
Also, there's an assumption that the landscape doesn't change unless all or most of the conference starts playing lacrosse (apologies if I'm putting words in anyone's mouth, but it sure reads that way). One major P5 school jumping in, especially if it's in a current or soon-to-be recruiting hotbed, changes the equation significantly for a number of reasons. If Texas launches a program, a number of kids who aren't totally crazy about football or whose parents are fearful of CTE or whose families struggle financially are gonna put down the pigskin and pick up a vulcanized rubber ball.